Some 98,000 West Island, St. Laurent and off-island households received a notice in their mailbox last week, telling them how they can register to claim compensation for the alleged effects of sulphur trioxide cloud released from a Valleyfield zinc smelter in 2004.

The number of people eligible to be included in the class action lawsuit might rise from the current 180,000, if Quebec Superior Court authorizes the geographic area affected by toxic levels of the chemical to be broadened.

“The path of the toxic cloud will have to be redrawn,” Chantal Desjardins told The Suburban in an electronic mail reply to questions. The lawyer, who pleaded the alleged victims’ case in court, asserted that the company had argued that only 5.9 tonnes of sulphur dioxide were emitted, late on the night of August 9, 2004.

“We now know that at least 10 tonnes were indeed released as stated by the representatives of the company themselves, which will significantly increase the concentration [that residents were exposed to],” Me. Desjardins claimed.

“The dispersion model that we used was [calculated based on the release of] 5.9 tonnes over 32 minutes,” she explained. “We now know that it was 10 tonnes released over 20 minutes. The more gas released per minute, the higher the concentration [in the air].”

Becomes sulphuric acid when inhaled

If the court agrees, that would vastly increase the number of people alleged to have been exposed to toxic levels of sulphur trioxide as the cloud passed over Montreal on a warm summer night when many slept with their windows open.

The gas is usually captured as part of the normal process of zinc smelting, and not released into the atmosphere.

It turns to sulphuric acid when it is inhaled into the lungs, which are moist. Those sulphuric acid molecules are larger than the sulphur trioxide molecules, hence more difficult to exhale.

“There have been no other releases over the years,” Liana Centomo, director of technology and environment at Canadian Electrolytic Zinc told The Suburban in an interview. The chemical engineer explained that the Valleyfield plant has used the same smelting process for a half-century.

Ms. Centomo claimed that “the concentration within the radius of the plant, which is not even in the West Island, could lead to minor [discomfort], but that it would be a very short-lived thing.”

“We have information that a few—maybe a dozen—people went to hospital but were released that evening with no consequences.”

“We’re a company that is recognized as a leader in the environment,” she added, “and we pour money into the plant to make sure that things run safely and improve safety and care for the environment.”

Claims could rise to billions

“The cloud exposed more than two million people,” claimed Me. Desjardins. “We have received thousands of e-mails from people who are currently excluded [from the class action lawsuit]. That is why the website www.nuagetoxique.com is currently inviting them to register as ‘excluded’.”

People who register will receive newsletters about the progress of the class action.

The lawsuit asks the court to order the company to pay $5,000 each for most individuals who were allegedly affected. It also is asking for $10,000 compensation for each person who suffered “an asthma crisis”.

“The presumption of good faith,” means that most people won’t have to undergo a medical exam to prove that they were affected, said Me. Desjardins, who added that non-residents who were in the designated areas at the time that the cloud passed over are also eligible to register.

“Positively no medical proof will be required subsequently,” she emphasized, explaining that the legal term ‘bodily insecurity’ pertains to exemplary damages for infringing upon claimants’ constitutional rights.

“[Most] members [of the class action lawsuit will be] taken at their word,” she added.” Those who suffered asthma attacks might have to prove their medical condition [though], in order to claim the $10,000.”

If Quebec Superior Court agrees that a broader geographic area was exposed to toxic levels of sulphur trioxide than was believed when it authorized the class action to proceed, claims in what is already the largest environmental lawsuit in Canadian history could rise to many billions of dollars.